Saw-mill set-works



UNITE STATES PATENT @nrrcn.

ROBERT It. PARSONS, OF J AOKSON, MISSISSIPPI.

SAW-MI.LLSET:WORK S.

SPECIFICATION forming part of Letters Patent No. 296,4d2, dated April 8, 1884. Application filed Novemberl), 1883. (No model.)

To aZZ whom it may concern.- I

Be it known that I, ROBERT R. Pnnsons, of Jackson, in the county of Hinds and State of Mississippi, have invented a new and Improved Head-Block for Saw-Mills, ofwhich thefollowingis a full, clear, and exact description.

This invention pertains to improvementsin head-blocks for saw-mills; and it consists of the sundry combinations and arrangements of parts, substantially as hereinafter fully set forth and clai med.

Reference is to be had to the accompanying drawings, forming part of this specification, in which similar letters of reference indicate corresponding parts in all the figures.

Figurel is aplan view of part of a log-can riage with a head-block and setting apparatus arranged according to my invent-ion. Fig. 2 is a side elevation. Fig. 3 is'a longitudinal sectional elevation through the headblock and knee on the line a m of Fig. 1. Fig. 4: is a section of the stop device on line y Fig. 1, with the pawls in front of said line dotted in. Fig. 5 represents adetail of the tripping device of the set-ting-pawls in side elevation and in section. Fig. 6 represents the stop wheel and pin in side elevation.

With each head-block c, I arrange a short shaft, 12, in hearings in the head-block, and gear said shaft with therackd of the knee 6 by a pinion, f. On each shaft 11 I arrangea coiled spring, 9, one end of which is connected to the head-block, and the other end is connected to the shaft by an arm, k, or other suitable device. The' springs are so adjusted that when the knees are shifted by the setting-shaft i and pinion j, the springs will be wound up with sufficient tension to shift the knees back quickly when allowed to act, which is to be done by tripping the settingpawls each time a log is finished and another is to be put on the carriage. The settingflshaft i is geared by the bevehwheels k with the ratchet-wheel l, which is operated by means of reversely-acting pawls on opposite sides of its axis, connected by rods m with the cross-head a of a sliding bar, 0, arranged in suitable guides, 17,

attached to one of the carriage-timbers, q, and having a rack, s, gearing with atoothed segment, 1, to which the setting-lever a is attached. The pawls consist of a radially-slid ing catch, w, arranged in the head 2 of a pawlarm, at, working on the hub of the ratchet- ,wheel I, and having a spring, 3 to bear it into contact with the ratchet-wheel, the pawl-arm being connected to rod on, to be oscillated by the slide 0 and setting-lever a. To trip the pawls when the knees are to be shifted back by the springs, the catches w havea notch in one side, forming a shoulder at a, under which a slide, b, dovetailed in a groove, 0, of the pawl-arm m, transversely of the catch, and having an incline, c, which worksto raise the catch out of the notchesof the ratchet-wheel, or allow it to shiftwith them, according as said slide is shifted one way or the other by the hand-lever cl,pivoted at e on the center of the cross-head'n, and having the trip-slides b of both pawls connected to it by rods f, said "rods being connected on the opposite sides of the center of said lever to be operated reversely in accordance with the reverse action of the pawls, so that when the lever d stands in one position both pawl catches will be engaged with theratchet-wheel, and both will be tripped when the lever is shifted to the reverse position. The setting is effected by moving lever a a certain distance forward-say to the right-pushing ratchet-wheel Z by the upper pawl, and then pushing the lever back to the startingpoint and pushing the ratchet by the lower pawl. The range of these movements will be limited by stop-pins g,to be set as required in the holes 71/ of slide 0, for contact with the guide-block p, or any other suitable fixed object. WVhen these springs g are used to shift back the knees, it is desirable to prevent them from shifting the knees back too far, and it is alsodesirable to stop the knees at different points along the head-blocks for logs of different sizes, so that no time will be lost in setting the log to the position for the first cut. I have therefore arranged a stopwheel, i, on a bracket, j, attached to the carriage-timber q alongside of one of the head blocks, which wheel has a series of holes, is, in a circle near the periphery, and it gears with a pinion, Z, on the setting-shaft i, so as to be rotated by said shaft. When the knees shift back, a stop-pin, m, is to be set in any one of the holes 70', according to the extent the knees are to shift back, and this pin is to be stopped by the horn n of a buffer-slide, 0,

fixed in suitable guides, p and q, of the bracket,

and having astrong buffer-spring, t, fixed between its head a and the inner end of the bracket j, to yield slightly under the shock, but having sufficient power to stop the knees at the desired point.

' In sawing very large logs it may sometimes occur that the wheel 1' will require to make more than one turn in the'setting of the logs, so that the stop-pin m will require to pass the horn a if not taken out of'the wheel. The bar 0 is therefore arranged to be pushed along in its bearings p q, to allow the pin to pass, and a tight spring, 10, is fitted on the bar to shift it back till the buffer-spring t stops it in itsplace again. The pin m will in such case have to be taken out to let the knees be shifted back, and will require to be readjusted again.

I prefer to employ a spring, with each headblock; but one spring connected with the knee of one head-block may, if sufficiently powerful, serve to shift the knees back, and it will take up the slack of all the setting-gear, ex-

cept between the knee-racks and pinion of the.

other head-blocks.

Having thus described my invention, What I claim as new, and desire to secure by Letters Patent, is

1. In headblocks for saw-mills, the combination, with the head-block having on its under side a rack, and the setting-shaft geared with said rack, of the shaft having its bearing in the head-block and geared with said rack, and a spring applied thereto and to the head-block, substantially as and for the purpose set forth.

2. In a saw-mill head-block, the head-block having on its under side a rack, the settingshaft geared with said rack, and the shaft geared with the said rack, and having a spring applied thereto and to the head-block, in combination with the ratchet-wheel, whose shaft is geared with the setting-shaft, and the handlever having a toothed segment gearing with the rack of a sliding bar carrying the ratchetwheel-operating mechanism, substantially as and for the purpose set forth.

3. In a saw-mill head-block, the combina tion, with the setting-shaft geared with the head-block, and the shaft having a spring applied thereto and to the head-block, said shaft being geared with the head-block rack, of the stop-wheel having a series of pin-holes and the buffer-slide having a horn, a buffer-spring, and a supplementary spring to return the bufferslide to its normal position after the movement of the horn out of the plane of movement of the pin of the stop-wheel, substantially as and for the purpose set forth.

4. In a saw-mill head-block, the setting-shaft geared with the head-block and with the shaft carrying a ratchet-wheel, and the shaft geared also with the head-block, and having a spring applied thereto and to the head-block, in combination with the sliding bar having stops, one on each side of one of its guides, and carrying a lever provided with pawls engaging with said ratchet-wheel, the hand-lever having a toothed segment gearing with a rack on said sliding bar, the stop-wheel having a stoppin, and the spring buffer-bar having a horn,

substantially as and for the purpose set forth.

5. In a saw-mill head-block, the combination, with the pawl-arms connected centrally to the axis of the ratchet-wheel and to a centrally-pivoted lever, and spring-catches fitted to slide vertically in the pawl-arm heads, of the slides fitted to slide in the latter and in the catches at right angles to the plane of movement of said catches, and having at intermediate points between their ends notches'or recesses with inclined surfaces, said slides being connected to a hand-lever centrally pivoted upon the aforesaid lever, substantially as and for the purpose set forth.

6. In a saw-mill head-block, the combina tion, with the stop-wheel having a stop'pin and gearing with the setting-shaft, of the sliding spring buffer-rod having the horn, and the supplementary readjustingspring connected to a fixed point and to the sliding buffer-rod, substantially as and for the purpose set forth.

7. The stop-wheel 6, having a series of pinholes, k, and the buffer-slide 0, having horn n, and buffer-spring t, in combination with the setting-shaft i and the knees 6, having springs g, for shifting the knees back, said wheel a" being geared with said setting-shaft, substantially as described.

ROBT. R. PARSONS.

Witnesses:

GEO. FRASER, HENRY STRAUSS. 

